A hotly contested, supposedly ancient manuscript suggests Christ was married. But believing its origin story—a real-life Da Vinci Code, involving a Harvard professor, a onetime Florida pornographer, and an escape from East Germany—requires a big leap of faith.

On a humid afternoon this past November, I pulled off Interstate 75 into a stretch of Florida pine forest tangled with runaway vines. My GPS was homing in on the house of a man I thought might hold the master key to one of the strangest scholarly mysteries in recent decades: a 1,300-year-old scrap of papyrus that bore the phrase “Jesus said to them, My wife.” The fragment, written in the ancient language of Coptic, had set off shock waves when an eminent Harvard historian of early Christianity, Karen L. King, presented it in September 2012 at a conference in Rome.

Never before had an ancient manuscript alluded to Jesus’s being married. The papyrus’s lines were incomplete, but they seemed to describe a dialogue between Jesus and the apostles over whether his “wife”—possibly Mary Magdalene—was “worthy” of discipleship. Its main point, King argued, was that “women who are wives and mothers can be Jesus’s disciples.” She thought the passage likely figured into ancient debates over whether “marriage or celibacy [was] the ideal mode of Christian life” and, ultimately, whether a person could be both sexual and holy.

King called the business-card-size papyrus “The Gospel of Jesus’s Wife.” But even without that provocative title, it would have shaken the world of biblical scholarship. Centuries of Christian tradition are bound up in whether the scrap is authentic or, as a growing group of scholars contends, an outrageous modern fake: Jesus’s bachelorhood helps form the basis for priestly celibacy, and his all-male cast of apostles has long been cited to justify limits on women’s religious leadership. In the Roman Catholic Church in particular, the New Testament is seen as divine revelation handed down through a long line of men—Jesus, the 12 apostles, the Church fathers, the popes, and finally the priests who bring God’s word to the parish pews today.

King showed the papyrus to a small group of media outlets in the weeks before her announcement—The Boston Globe, The New York Times, and both Smithsonian magazine and the Smithsonian Channel—on the condition that no stories run before her presentation in Rome. Smithsonian assigned me a long feature, sending me to see King at Harvard and then to follow her to Rome. I was the only reporter in the room when she revealed her find to colleagues, who reacted with equal parts fascination and disbelief.

“The Gospel of Jesus’s Wife” papyrus (Karen L. King / Harvard / AP)

Within days, doubts mounted. The Vatican newspaper labeled the papyrus “an inept forgery.” Scholars took to their blogs to point out apparent errors in Coptic grammar as well as phrases that seemed to have been lifted from the Gospel of Thomas. Others deemed the text suspiciously in step with the zeitgeist of growing religious egalitarianism and of intrigue around the idea, popularized byThe Da Vinci Code, of a married Jesus. The controversy made news around the world, including an article in these pages.

A year and a half later, however, Harvard announced the results of carbon-dating tests, multispectral imaging, and other lab analyses: The papyrus appeared to be of ancient origin, and the ink had no obviously modern ingredients. This didn’t rule out fraud. A determined forger could obtain a blank scrap of centuries-old papyrus (perhaps even on eBay, where old papyri are routinely auctioned), mix ink from ancient recipes, and fashion passable Coptic script, particularly if he or she had some scholarly training. But the scientific findings complicated the case for forgery. The Gospel of Jesus’s Wife had undergone—and passed—more state-of-the-art lab tests, inch for inch, than almost any other papyrus in history.

But skeptics had identified other problems. Among the most damning was an odd typographical error that appears in both the Jesus’s-wife fragment and an edition of the Gospel of Thomas that was posted online in 2002, suggesting an easily available source for a modern forger’s cut-and-paste job.

With King and her critics at loggerheads, each insisting on the primacy of their evidence, I wondered why no one had conducted a different sort of test: a thorough vetting of the papyrus’s chain of ownership.

King has steadfastly honored the current owner’s request for anonymity. But in 2012, she sent me the text of e-mails she’d exchanged with him, after removing his name and identifying details. His account of how he’d come to possess the fragment, I noticed, contained a series of small inconsistencies. At the time, I wasn’t sure what to make of them. But years later, they still gnawed at me.

The American Association of Museums’ Guide to Provenance Research warns that an investigation of an object’s origins “is not unlike detective work”: “One may spend hours, days, or weeks following a trail that leads nowhere.” When I started to dig, however, I uncovered more than I’d ever expected—a warren of secrets and lies that spanned from the industrial districts of Berlin to the swingers scene of southwest Florida, and from the halls of Harvard and the Vatican to the headquarters of the East German Stasi.

The owner of the Jesus’s-wife fragment, whoever he was, had told King a story about where, when, and how he’d acquired it. But the closest thing he had to corroboration was a photocopy of a signed sales contract. The contract recorded his purchase of six Coptic papyri, in November 1999, from a man named Hans-Ulrich Laukamp. The contract said that Laukamp had himself acquired the papyri in Potsdam, in Communist East Germany, in 1963.

The owner also gave King a scan of a photocopy—that is, a copy of a copy—of a 1982 letter to Laukamp from Peter Munro, an Egyptologist at Berlin’s Free University. Munro wrote that a colleague had looked at the papyri and thought one of them bore text from the Gospel of John.

The only written reference to the Jesus’s-wife papyrus appeared in yet another scan—of an unsigned, undated, handwritten note. It said that Munro’s colleague believed that “the small fragment … is the sole example of a text in which Jesus uses direct speech with reference to having a wife,” which “could be evidence for a possible marriage.”

Perhaps conveniently, every player in this story was dead. Peter Munro died in 2009, the colleague he had supposedly consulted about the papyri died in 2006, and Hans-Ulrich Laukamp died in 2002. King thus declared the scrap’s history all but unknowable. “The lack of information regarding the provenance of the discovery is unfortunate,” she wrote in 2014, in an article about the papyrus in the Harvard Theological Review, “since, when known, such information is extremely pertinent.”

But was there a lack of information? Or just a lack of investigation? The owner, for one, was still alive and had known Laukamp personally, King told me in 2012. In one e-mail to King, the owner wrote that Laukamp had “brought [his papyri] over when he immigrated to the USA.” That suggested that Laukamp had sold them while living in America.

I searched public documents and found just one American city that had ever been home to a Hans-Ulrich Laukamp. In 1997, a German couple named Hans-Ulrich and Helga Laukamp had built a single-story stucco house with a swimming pool in the Gulf Coast city of Venice, Florida.

I tracked down people who had known the Laukamps, and they told me that the couple were chain smokers with almost no grasp of English; they were loners in a middle-income enclave of bike-riding “active seniors.” Helga had worked in a laundry, and Hans-Ulrich was a toolmaker who had never finished high school—not the background I was expecting for a manuscript collector.

The Laukamps might never have left their small Berlin apartment were it not for a late-in-life reversal of fortune. In 1995, Laukamp and his friend Axel Herzsprung, a fellow toolmaker, went into business together. The company, ACMB Metallbearbeitung GmbH, or ACMB Metalworking, won a lucrative contract to make brake components for BMW and was soon drawing profits of about $250,000 a year.

Laukamp, then in his mid-50s, bought a Pontiac Firebird and nudged Herzsprung and his wife to build a vacation home next to his in Florida, where the Laukamps hoped to one day retire. But those dreams evaporated almost as soon as they landed in the Sunshine State. Helga was diagnosed with lung cancer, and Hans-Ulrich took her back to Germany, where she died in December 1999 at the age of 56. The company filed for bankruptcy in August 2002, and Hans-Ulrich died four months later, at 59, after lung cancer metastasized to his brain.

Looking over his company’s public records, I spotted a peculiar detail. Four days after Laukamp’s wife died in a Berlin hospital, his auto-parts company incorporated an American branch, using the address of an office building in Venice, Florida. What’s more, Laukamp and Herzsprung weren’t the American business’s only officers. There was a third man, someone named Walter Fritz, who’d come to Florida from Germany at least four years before the other two and who would soon strike both men from the corporate documents, leaving him as the sole director of the American branch.

Walter Fritz still lived in Florida, and on paper he looked like an unremarkable local: 50 years old, married, with a single-story house in North Port, 30 minutes east of Venice. If Fritz stood out for anything, it was his civic ardor. He wrote eloquent letters to the editor of the North Port Sun. He led neighbors in a successful protest against overhead power lines. He was a regular at the 7:15 breakfasts of the North Port Early Bird Kiwanis Club. And when city commissioners gathered to hash out North Port’s annual budget, Fritz—a tall, lean man with chiseled features and dark hair, to judge by a video of the meeting—sat through hours of tedious discussion for a chance to harangue the elected leaders about a proposed recession-year tax hike.

When I ran Fritz’s name through a database of Florida incorporations, I found that the auto-parts firm wasn’t the only business he had ties to. In 1995, Fritz had founded a company called Nefer Art. Nefer is the Egyptian word for “beauty.” If someone close to Laukamp had an affinity for Egyptian art, that person was worth talking to: Coptic was an Egyptian language, and nearly all ancient papyri come from Egypt.

I ran Walter Fritz and Egypt through some search engines, and one hit caught my eye: In 1991, someone named Walter Fritz had published an article in a prestigious German-language journal, Studien zur Altägyptischen Kultur, orStudies in Ancient Egyptian Culture. He had used infrared photography to decode textual minutiae on a 3,400-year-old Egyptian tablet. The journal listed his affiliation as the Egyptology institute at Berlin’s Free University—the very place that had also employed Peter Munro and his colleague who had supposedly examined Hans-Ulrich Laukamp’s papyri in 1982.

I wondered whether the author of the article and the Florida auto-parts executive could possibly be the same man. I called several prominent Egyptologists, who told me that the article—which had reoriented a debate over whether Akhenaten and his father served alone as pharaohs or together as co-regents—remained influential. But none of them—not even the journal’s former editors—could recall who Walter Fritz was or what had become of him.

I flew to florida in November to learn more about Laukamp, but Fritz had come to seem almost as interesting. I planned to knock on his door with some questions. But when I pulled up to Fritz’s three-acre lot, my heart sank: The property had no bell or intercom, just a forbidding gate at the end of a driveway that snaked behind a curtain of muscadine vine and Virginia creeper. A twitchy brown dog watched me from beneath a no trespassing sign. I idled my rental car outside the gate, considered my options, and then drove back to my hotel.

I called Fritz the next morning and told him I was in town working on a story about Laukamp and the Jesus’s-wife papyrus. I asked to meet him. He abruptly declined, grew agitated, and made clear he wanted to get off the phone.

He had never studied Egyptology at the Free University, he said. He had never written an article for a German journal. Though the Web site for Laukamp and Herzsprung’s business had listed Fritz as the president of its U.S. branch, he told me he was in fact just a consultant who had helped get the company incorporated. He couldn’t even recall how he’d met Laukamp.

But when I asked whether Laukamp had been interested in antiquities, Fritz bristled. “He was interested in a lot of things,” he said.

Like what?, I asked.

“I know he had a beer-mug collection.”

He then alluded, somewhat cryptically, to the question of the papyrus’s authenticity. “There will always be people who say yes and people who say no,” he told me. “Everybody is up in arms and has an opinion.”

I asked him what his opinion was.

“I don’t want to comment.”

Are you the owner?, I asked.

“No,” he said. “Who said that?”

No one, I answered, but since he was one of Laukamp’s few American acquaintances, I wanted to be sure.

He wasn’t the owner, Fritz insisted. He had no idea who was.

Karen king is the first woman to hold Harvard’s 295-year-old Hollis Professorship of Divinity, one of the country’s loftiest perches in religious studies. The daughter of a pharmacist and a schoolteacher from a Montana cattle town, King enrolled at the University of Montana, where a course on marginalized Christian texts spoke to her in almost personal terms. “I already had this sense of not fitting in,” King told me in 2012. “From grade school on, I was the kid who was picked on,” she said. “I thought if I could figure out [these texts], then I could figure out what was wrong with me.”

She earned a doctorate in the history of religions from Brown in 1984 and by 1991 had become the chair of both religious studies and women’s studies at Occidental College. Harvard Divinity School hired her in 1997.